Light emitting diode is a kind of optoelectronic semiconductor component which can convert current into light having a specific wavelength range. The light emitting diodes have high brightness, low voltage, low power consumption, simple drive, long life and other advantages, and easily match with integrated circuits, so the light emitting diode is widely used as a light source. The light emitting diode is usually coated with a lens around it for secondary optical correction after encapsulation.